Your restaurant AI booking agent needs a facts file before it takes one reservation

Four days after I wired a booking agent into the reservations inbox of a 40-seat restaurant, it had quoted a caller "$45 per person, all in, drinks included" for a set menu that actually runs $68. In the same thread it promised a same-day cancellation policy the restaurant has never offered. The caller arrived expecting both, and the manager had to choose between eating a $23-a-head mistake or starting the evening with an argument.

The agent didn't invent those numbers because it was stupid. Ask a language model for a price it was never given and it will produce the most plausible number it can. Plausible is the problem: the customer can't tell the difference until they are standing at the door.

A restaurant agent is not a general assistant. It is a quoting machine for facts that change weekly. It should be treated like one.

Why restaurants are uniquely exposed

Every industry has gaps in its facts. Restaurants have more of them, and the gaps sit exactly where money and safety meet.

• Prices move constantly. Market fish, a seasonal menu, a new wine list. The number that was right in March is wrong in June, and nobody re-pastes the website.
• Set menus are conditional. "The set menu is $68" is incomplete. It is $68 per person, minimum four people, 48 hours' notice, and a different price on a Saturday.
• Deposits and cancellation are the two most-disputed sentences in hospitality. Get them wrong and you are either refunding money you shouldn't or arguing about money you should keep.
• Allergen questions are a health and legal problem, not an FAQ. One wrong "yes, it's dairy-free" is not a service failure; it is an incident nobody wants to be explaining later.
• The customer is time-pressured and on a phone. They want a number and a time, now, and they will act on whatever you tell them.

That is the whole case for a facts file. The questions that cost you money and create liability are precisely the questions a model is most tempted to improvise.

The restaurant facts file

One plain-text file. Three sections, in this order. Every line self-contained, so the agent can lift it into an answer word for word.

[FACTS]
Set menu ("Chef's Table"): $68 per person, minimum 4 people, 48 hours' notice.
Set menu Saturday: $78 per person, minimum 4.
A la carte mains: $22-$39.
House wine by the glass: $11-$16. Corkage $25 per bottle, max 2 bottles.
Business hours: Tue-Thu 17:00-22:00, Fri-Sat 17:00-23:00, Sun 12:00-21:00. Closed Monday.
Kitchen last orders: 30 minutes before close.
Booking lead time: 2 hours minimum, 60 days maximum.
Standard tables seat up to 6. Parties of 7-14 book the private room.
Private room minimum spend: $1,200 food and beverage Tue-Thu; $1,800 Fri-Sat.
Deposit: $20 per person for parties of 8+, refundable if cancelled 72+ hours ahead.
Cancellation: free up to 24 hours before the booking. Inside 24 hours the deposit is not refunded.
Children: 2 high chairs available. Under-5s eat free from the kids' menu on Sundays.
Accessibility: step-free entrance on Oak Street. Accessible restroom.
Parking: street only. Nearest public lot is a 2-minute walk.
Holiday closures 2026: Dec 24, Dec 25, Jan 1. Dec 31 closes at 20:00.

[RULES]
Quote only facts listed in [FACTS]. If a fact is not listed, say you will check with the team.
Never invent prices, discounts, or policies.
Never confirm or deny a refund or a deposit return. The manager decides.
Never answer allergen or dietary-safety questions in your own words.
Never promise a table, time, or menu change the booking system has not confirmed.
Take one booking per conversation and read the details back to the customer.

[ESCALATE IF]
Customer asks whether a dish is safe for an allergy, intolerance, or medical condition.
Customer asks for a discount, a comped dish, or an exception to a minimum spend.
Customer asks to change, cancel, or refund a deposit.
Customer reports being unwell after eating here.
Customer raises a complaint about a previous visit.
Customer asks for a same-day booking for 10 or more people.
Customer asks anything about the menu, hours, or policy that is not in [FACTS].

Two lines do most of the work. "Quote only facts listed in [FACTS]" turns the agent from a business expert into a careful reader, which is what you want in front of a paying guest. And every [ESCALATE IF] line does two jobs: it tells the agent to hand off, and — more importantly — it tells the agent that this class of question is not its to answer. The moment "allergen" appears in that section, the model stops answering and starts deferring. That flip is the whole game for anything health-related.

The questions that do the most damage

Four mistakes I see on almost every restaurant build

1. Treating the set menu as a single price. It is a price, a minimum, a lead time and a day-of-week rule. List all four, or the agent will quote one and invent the rest.
2. Putting hours in three places. If the hours live in the prompt, the website and the booking tool, they will disagree within a month. One file is the source of truth; everything else reads from it.
3. Letting the agent confirm bookings it cannot see. If it cannot read the reservation calendar, it cannot promise a table. Give it the calendar, or make it a request-taker rather than a booker.
4. Handing off without context. An escalation that arrives as "customer asked about a refund" makes the human start from zero. Send name, summary, what was tried, what's open and a suggested reply.

What to do today

• Write the [FACTS] block from your last 20 real reservation messages. That is your true question set.
• Add "Quote only facts listed in [FACTS]" to the system prompt before the next message goes out.
• Move every money, allergy and complaint trigger into [ESCALATE IF], and delete the ones that merely route.
• Put hours, set-menu terms and the deposit policy in one file, and make it the only copy.
• Run 20 hostile messages — price fishing, "the manager always gives me 20% off", allergen traps — before the agent talks to a real guest again.

None of this needs a new model or a new vendor. It needs one file that says what is true, one rule that says stick to it, and one section that says when to stop.